Green Building Design

Scott LoweProfessor

Civil and Environmental Engineering Department

Manhattan College

Buildings are Complex Systems !

1. Site

• High density urban

• Extreme slope

A Green Site?

• Brownfield

Not Green

• Pristine land

2. Foundations

• Building load must be spread out or transferred to rock

• Footings• Piles• Caissons

3. Frame

• steel

• Reinforced concrete

• wood

3. Electrical

4. Mechanical

• HVAC

5. Plumbing

• Water supply– Cold water– Hot water

• Wastewater collection• Heating pipes• Gas• Fire system

6. Interior

• floors

• Internal walls• Finish – walls/floor

7. Exterior

How Green is my Building?

• US Green Building Council established the LEED rating system in 1998

• Leadership in Energy and Environmental Design

• Points system

LEED System (New Building)

• Site (26 pts)• Water (10 pts)• Energy (35 pts)• Materials (14 pts)• Indoor Quality (15 pts)

• Rating out of 100• 40-49 certified• 50-59 silver• 60-79 gold• 80+ platinum

LEED Site example

• Bike racks• Changing rooms

LEED Water example

• landscaping

LEED Energy example

• Generate energy

LEED Materials example

• recycled

LEED Indoor Quality example

• Natural light

Energy

• Buildings consume massive amounts of energy• 40% of all US energy• 70% of all US electricity• Where is it used?

Sizzling Hot Energy Topics

• Do it more efficiently• Generate your own• Keep your heat but• Don’t lose your cool

EfficiencyEfficient HVAC systems

– Use high efficiency systems– 90%+ possible– High capital cost– Will pay this back – Not sexy

Create Energy

• Solar - active

Solar - passive• Trombe wall

Solar – hot water

Geothermal

• ~6 ft below ground the temperature is ~50OF all year

• Run water pipes through ground• In summer hot water enters ground – cool

exits• Use this to cool air for the HVAC system• In winter reverse process

GeothermalPipingInstallation~6 ft underground

CEEN201: Green Building Design

Excavation for geothermal pipe field

CEEN201: Green Building Design

Geothermal heat exchanger

CEEN201: Green Building Design

Geothermal heat exchanger

CEEN201: Green Building Design

Geothermal lake construction

Sherman Hospital Illinois

Keep Your Heat

• and don’t lose your cool• Insulate, insulate, insulate !!!!!!!!!!!!!!!!!!• Biggest bang for your $

Heat Transfer 101

• Heat moves from hotcold• Driven by temp gradient• Analogous to fluid flow (high P to low P)• And dispersion (high Conc. to low Conc.)

Q = A DT R

Q = heat flow Btu/hrDT = temp difference oFA = wall area ft2

R = resistance oF - ft2 / (Btu/hr)

Insulation

• Typical building codes– Walls R-19– Roofs R-30

• R values for each layer is added up

R Value of a house exterior wall• ½” sheetrock + 3 ½ “

insulation + ½” plywood + wood siding + tyvek

• R = 0.45 + 11 + 0.63 + 0.8 + 0.85

• R value = 13.73

Windows

• Poor insulators• Building Code = double pane• Leaks are a problem• Single pane of ¼” glass, R= 0.9• With storm, R=2• Double pane ~2• Triple pane ~3

Water

• Water supply• Under pressure

Collection System

• Only 1 drainage system• Toilets• Shower• Bath• Sinks• Laundry• Dishwasher• Floor drains

Black and Grey water

Black• Can NEVER be reused• Goes to sewer system

• Toilet• Kitchen sink• Dish washer

Grey• Can be reused but NOT for

drinking• Flush toilets, water gardens

• Shower• Wash basin• Laundry

Complex to re-plumb existing buildings

• Need to create 2 drainage systems

• Need to store and distribute grey water

• Tanks and pumps• Clean water back-up in

case not enough grey water

• Etc,etc

Roofs can be Green

• Or black or white or blue

White Roof

Blue Roof

The End

• Bank Of America Tower• 1200 ft tall, 55 floors• 2.1 million ft2

• LEED platinum